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Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

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Describe the approximate term of the guarantee or each group of similar guarantees.

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Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income.

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Commitments and Contingencies (Details) (USD $)	12 Months Ended
Commitments and Contingencies (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Commitments and Contingencies
Rent expense	$ 25,200,000us-gaap_OperatingLeasesRentExpenseNet	$ 25,000,000us-gaap_OperatingLeasesRentExpenseNet	$ 22,000,000us-gaap_OperatingLeasesRentExpenseNet
2015	14,479,000
2016	11,040,000
2017	9,531,000
2018	5,544,000
2019	3,434,000
Thereafter	18,641,000
Total future minimum rental payments	62,669,000
Schedule Of Guarantees
Maximum potential undiscounted payments	251,265,000
Performance guarantees through letters of credit
Schedule Of Guarantees
Term	2015-2019
Maximum potential undiscounted payments	142,785,000
Standby letters of credit
Schedule Of Guarantees
Term	2015
Maximum potential undiscounted payments	12,910,000
Commercial letters of credit
Schedule Of Guarantees
Term	2015
Maximum potential undiscounted payments	9,192,000
Bid bonds and performance bonds
Schedule Of Guarantees
Term	2015-2023
Maximum potential undiscounted payments	$ 86,378,000